Folding boom



Dec. 29, 1959 Filed July 6, 1956 J. W. HALBROOK ETAL FOLDING BOOM 3 Sheets-Sheet 1 William 0. Knaa/r INVENTORS,

Dec. 29, 1959 J. w. HALBROOK ET AL 2,919,107

FOLDING BOOM Filed July 6, 1956 I 3 Sheets-Sheet 2 Fig. 8

32 \x fs/ James W. Ha/broo/r William 0. Knaa/r INVEN TORS,

M4062 M W zzw Dec. 29, 1959 J. w. HALBROOK ETAL 2,919,107

FOLDING BOOM Filed July 6, 1956 3 Sheets-Sheet 3 William 0. Knaak 65 INVENTORS,

United States Patent @fiice 2,919,107 Patented Dec. 29, 1959 FOLDING BOOM James W. Halbrook and William 0. Knaak, Corpus Christi, Tex.

Application July 6, 1956, Serial No. 596,355 Claims. (Cl. 254-1391) This invention relates to a folding boom usable as a boom, stepladder or like devices.

An object of the present invention is to provide a folding device, termed a boom which is capable of being used as a stationary equipment or as a mobile equipment on a motor vehicle, the unique feature of the invention being the simplicity of the folding apparatus.

An object of the present invention is to provide a boom which is capable of being mounted on a motor vehicle for mobility, the boom including a first and a second boom member pivotally connected and capable of automatically folding to an inoperative position on the motor vehicle and of being actuated to an extended, operative position upon application of a force through a single wire or rope cable, chain or other flexible elongated device.

A more specific object of the present invention is to provide a boom which has a first, lower boom member pivoted to a second boom member, these members being arranged in alignment when in the operative position and held in alignment by means of a single locking pin, this being the only device that must be removed or manually adjusted to have the boom lowered to a folded position, at which the boom members as well as a pair of risers which support the boom members in the aligned position, come to rest upon a support that is provided on the motor vehicle adjacent to the power winch used to wind and pay out the cable as considered necessary or desirable by the truck operator in the use of the invention.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a fragmentary elevational view of a standard motor vehicle, a truck in this instance, having the invention applied thereon;

Figure 2 is an elevational view of the motor vehicle of Figure 1 and having a folding boom made in accordance with the principles of the invention applied thereto, the folding boom being in the inoperative, folded position;

Figure 3 is a rear elevational view of the motor vehicle and boom of Figure 2;

Figure 4 is a perspective view of the boom structure with the cable removed;

Figure 5 is an enlarged fragmentary sectional view taken on the line 5-5 of Figure 1;

Figure 6 is an elevational view as would be seen along the line 66 of Figure 1;

Figure 7 is a sectional view Figure 1;

Figure 8 is an elevational view taken the line 88 of Figure 2; and

Figure 9 is a sectional view Figure 1.

The folding boom 1%) which exemplifies the principles of the invention may be applied on a stationary support taken on the line 77 of approximately on taken on the line 99 of or, may be applied to a motor vehicle. Inasmuch as a mobile boom is more common, we have chosen to illustrate our folding boom on the bed of a truck 12 which typifies any type of motor vehicle. The truck has a pair of stringers 14 that constitute a part of the chassis on which base 16 is mounted. The base has sides 17 and 18 together with sufficient transverse support, as pipe 22. Hangers 23 and 24 depend from sides 17 and 18 and have a transverse bar 26 secured thereto. A pair of rails 30 and 31 are located between the sides 17 and 18 and are fixed to the cross members of the base 16. Rails 30 and 31 have a number of apertures 32 in order to provide a selection for pivotally securing the divergent ends of arms 36 and 37 thereto. For this purpose, spindle 40 is passed through a selected pair of apertures 32 and through apertures in the mounting plates 43 and 44 at the lower extremities of arms 36 and 37. Rollers 45 and 46 are on spindle 46 and rest on a flat part of the base 30 for reducing friction in changing the angle of the boom. For this construction, attention is invited to Figure 9 where the divergent ends of arms 37 and 36 are clearly illustrated. Plates 43 and 44 have apertures and have spindle 40 thereon which is in the form of a pipe or sleeve and which functions as a spreader for the divergent ends of arms 36 and 37. It may be spot welded thereto or otherwise fastened. The rollers 45 and 46 may be freely rotatable thereon or held spaced by means of spacer 50 so that they revolve in unison. Hold-down pin 51 passes through the aligned openings in rails 30 and 31, plates 43 and 44 and the bore of spindle 40.

When it is desired to change the angle of the boom, the hold-down pin 51 is removed and the lower extremities of the arms 36 and 37 are propelled forward or rearward on the base 16 to a position of alignment with a selected aperture 32. The hold-down pin is then replaced thereby pivotally attaching the diverged ends of arms 36 and 37 onto the base. The upper ends of arms 36 and 37 converge and are fixed to a lower, first boom member 53 that is made of a pair of parallel plates 54 and 55 between which the second, upper boom member 56 is disposed. Pivot pin 57 passes through aligned apertures in plates 54 and 55 and also in the boom member 56. The upper ends of plates 54 and 55 are beveled in order to match with a corresponding bevel on stops 59 and 6: that are fixed to the sides of the upper boom member 56. Cable guard 61 is fixed to plate 55, extending over pivot pin 57. The arrangement of stops 59 and 60 and the beveled upper ends of the first boom member is such that when the first and second boom members are in alignment as shown in Figures 1 and 4, the stops contact the beveled ends of the plates and retain the boom members in longitudinal alignment, preventing relative pivotal movement beyond this point of alignment but permitting return pivotal movement, to the position shown in Figure 2.

The lower end of the second boom member 56 extends between the arms 36 and 37 and has an angulated bracket 64 whose outer end has eye 65 in which hook 66 of pulley 67 is arranged. The opposite extremity of the second, upper boom member 56 has a pair of parallel plates 69 and 70 fixed to it. These plates are nested between plates 71 and 72 on the upper extremities of risers 73 and 74, the latter being in the form of an A-frame. There are means passed through the plates 70, 69, 72, 71 pivotally connecting these plates and thereby pivotally connecting the upper extremity of the second boom member 56 to the upper extremities of risers 73 and 74. The connecting means comprise pivot pin 75 on which there is a pulley 76. Plates 69 and 70 function as guides for the cable 36 which is passed over the pulley 76.

The lower ends of the risers 73 and 74 have plates 81 and 82 welded or otherwise rigidly secured thereto in Pivot pins 83 pass through these apertures and apertures in the sides 17 and 18 of base 16 thereby pivotally mounting the risers on the base that may be ,stationarily mounted or mounted on the truck as shown in Figure 1 and in Figure 2. Anordinary, standard winch 86 is mounted on the truck bed and has cable' 80 connected at one end thereto in order to be payed out or wound thereon. Standard controls for the winch are to be used in connection with it. The cable extends around pulley 67 and over pulley 76 and proceeds downwardly, terminating in a fastening device, as hook 88 which is adapted to be fastened onto the transverse bar 26.

In operation, after the boom is set up on a truck or in a stationary position, it is assumed that it is to be elevated to the operative position. In the lowered, inoperative position the two risers 73 and 74 are at rest on the stand 97 located adjacent to the winch 86 and rising which there are apertures.

slightly above the cab of the truck. The winch 86 is operated in such direction as to wind cable 80 thereon. As the cable winds it pulls over pulley -67, pulley 76 and against the anchored hook 88. Continued application of force by pulling the cable inwardly of winch 86 causes the boom members to be pivotally actuated about their pivot pin 57, with the relative pivotal motion continuing until the stops 59 and 60 are struck by the beveled end of the plates 54 and 55 of the first boom member 53. During this movement, there is a slight pivotal displacement of the two arms 37 and 36. In addition to this, there is an oscillation of the risers 73 and 74 about their lower pivots 83, the oscillation stopping when the risers reach the position shown in Figure 1.

When the cable 80 that is to be used for load lifting has raised the boom, the next step is' to insert locking pin 98 in the aligned apertures in the upper and lower boom members thereby holding the boom in the upright position'and in readiment for lifting loads.

In order to lower the boom, the hook 88 is engaged on transverse member 26 and a slight tension is applied to the line by operating the winch 86. The locking pin between boom members and to 98 is removed and the cable 80 is payed out allowing the weight of the boom assembly to cause the boom members to fold pivotally about pin 57- and the risers and arms to pivot correspondingly until the risers come to rest on the support 97.

,Although one embodiment of the invention has been illustrated and described, it is understood that the principles of the invention may be applied in other ways. For example, instead of the boom being made explicitly for lifting and lowering objects, it may be made with ladder members in lieu of the members 56 and 53 and used as a ladder. Other modifications as fall within'the scope of the invention as claimed may be resorted to.

What is claimed as new is as follows:

1. A folding boom comprising a base, a pair of legs having divergent ends pivoted to said base, a first boom member, said legs having a pair of convergent outer ends to which said first boom member is secured, a second boom member pivoted to said first boom member, means on said boom members to restrict the pivotal motion between boom members and to hold said members longitudinally aligned and prevent relative movement beyond a position of alignment, a pair of risers pivoted to said base, means at the outer ends of said risers pivotally securing said second boom member to said pair of risers, a cable, a winch to which one end of said cable is attached, a first cable guide carried by the inner end of said second boom member, a second cable guide located near the pivotal connection of said second boom member with said risers, said cable being entrained with said cable guides, and aload engaging device at the outer end of said cable which is adapted to in order to pivot said boom members into an aligned position in response to actuation of said winch, and a locking device releasably securing said boom members together, whensthey arein said aligned position.

be temporarily anchored 2. A folding boom comprising a base, a pair of legs having divergent ends pivoted to said base, a first boom member, said legs having a pair of convergent outer ends to which said first boom member is secured, a second boom member pivoted to said first boom member, means on said boom members to restrict the pivotal motion hold said members longitudinally aligned and prevent relative movement beyond a position of alignment, a pair of risers pivoted to said base, means at the outer ends of said risers pivotally securing said second boom member to said pair of risers, a cable, a winch to which one end of said cable is attached, a first cable guide carriedby the inner end of said second boom member, a second cable guide located near the pivotal connection 'of said second boom member with said risers, said cable being entrained over said cable guides, a load engaging device at the outer end of said cable which is adapted to be temporarily anchored in order to pivot said boom members into an aligned position in response to actuation of said Winch, a locking device releasably securing said boom members together when they are in said aligned position, said boom members being pivotally movable relative to each other when said locking device is released, and a support located adjacent to said winch on which said risers are adapted to rest when said boom members are pivoted to a rest position.

3. A folding boom, ladder or the like comprising a base, a first member pivoted to said base, a second member pivoted to said first member, means on said pivotal members including a stop for limiting the extent of pivotal movement of said members with respect to each other and in one direction, the extent of pivotal movement at which said members are limited being when said members are in longitudinal alignment, means for pivotally actuating said members to the aligned position, at least one roller at the pivotal connection between said first member and said base, said base provided with means for holding said first member for pivotal disposition in selected positions whereby the location of said members on said base may be preselected and when said first member is moved on said base said roller functions as a means to reduce friction, said means to pivotally actuate said members comprising a cable, a guide at the inner end of said second boom member around which said cable is entrained, a guide at the opposite end of said second boom member around which said cable is also entrained, and said cable having a device at its outer extremity to attach to a part of said base so that upon paying in said cable said first and second members are pivotally actuated to the aligned position.

4. A folding boom, ladder or the like comprising a base, a first member pivoted to said base, a second member pivoted between the ends of said first member, means on said pivotal members including a stop for limiting the extent of pivotal movement of said members with respect to each other and in one direction, the extent of pivotal movement at which said members are limited being when said members are in longitudinal alignment, means for pivotally actuating said members to the aligned position, at least one roller at the pivotal connection between said first member and saidbase, said base provided with means for holding said first member for pivotal disposition in selected positions whereby the location of said members on said base may be preselected and when said first member is moved on said base said roller functions as a means to reduce friction, said means to pivotally actuate said members comprising a cable, a guide at the inner end of said second boom member around which said cable is entrained, a guide at the opposite end of said second boom member around which said cable is also entrained, said cable having a device at its outer extremity to attach to a part of said base so that upon paying in saidcable-said first and second members are pivotally actuated to the aligned position and when References Cited in the file of this patent said device is detached from said base said cable func- UNITED STATES PATENTS tions as a means to lift a load and lower a load, a winch 1 024 665 B l t l A 30 1912 located adjacent to Said ba e and having Said cable P 7 4 939 iami; S g 2 1930 eratively connected thereto in der to P y in and P 5 5'5 4 Couse Nov 30 1943 out said cable in order to selec iv ly t and lower loads 509 435 H ni May 30 1950 Or to ere t the folding boom- 2:616:666 Honey Nov 4, 1952 5. The combination of claim 3 wherein there is a locking device between said first and second members in OTHER REFERENCES order to hold said members in the aligned position and 10 Powers American Pole-Master, Bulletin No. 405R. said members being automatically pivotable to the inop- Eublished by McCabe-Powers Auto Body Co. Received erative, non-aligned position upon release of said lockin Div. 4 of the U.S. Patent Oflice June 1, 1954. (Copy ing device. in Div. 61, class 254-1391.) 

